Corrosion monitoring in a fire sprinkler system

ABSTRACT

A fire sprinkler system according to one aspect of the present disclosure includes a pipe having a first pipe portion and a second pipe portion. The first pipe portion includes a wall having a first wall thickness, and the second pipe portion includes a wall having a second wall thickness that is greater than the first wall thickness. The fire sprinkler system further includes structure coupled to the pipe and defining a sealed chamber between the structure and at least the first pipe portion, and a sensor for sensing a pressure in the sealed chamber. Example corrosion monitoring devices and methods for monitoring corrosion in pipe systems, including fire sprinkler systems, are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/748,771 filed Jun. 24, 2015, which is a continuation of U.S.application Ser. No. 14/304,655 filed Jun. 13, 2014, which is acontinuation of International Application No. PCT/US14/37144 filed May7, 2014, which claims the benefit of U.S. Provisional Application No.61/820,439 filed May 7, 2013, and U.S. Provisional Application No.61/833,572 filed Jun. 11, 2013. The entire disclosures of the aboveapplications are incorporated herein by reference.

FIELD

The present disclosure relates to devices and methods for monitoringcorrosion in pipe systems, including fire sprinkler systems.

BACKGROUND

This section provides background information related to the presentdisclosure which is not necessarily prior art.

Water-based fire sprinkler systems are commonly used to protectbuildings, property and people from fire. There are two main types ofwater-based fire sprinkler systems: wet pipe sprinkler systems and drypipe sprinkler systems.

In wet pipe sprinkler systems, the piping network remains filled withwater until the system is actuated. If exposed to freezing temperatures,the water in the piping network may freeze and cause the piping networkto burst, resulting in substantial property damage and rendering thesystem inoperable. Therefore, wet pipe sprinkler systems are not wellsuited for applications involving freezing temperatures.

Dry pipe sprinkler systems can be used to protect unheated structuresand other areas where the system is subject to freezing temperatures.Dry pipe systems (including preaction systems) are also used inlocations where accidental water discharge from the system would behighly undesirable, such as museums, libraries and computer datacenters. In dry pipe sprinkler systems, the piping network is filledwith a pressurized gas (rather than water) until the system is actuated.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 is a side cross-sectional view of a corrosion monitoring assemblyin a fire sprinkler system according to one example embodiment of thepresent disclosure.

FIG. 2 is a side view of a pipe, a portion of which has a reduced wallthickness according to another example embodiment.

FIG. 3 is a side view of the pipe of FIG. 2 with a sleeve centered overthe reduced wall thickness portion.

FIG. 4 is a side view of a corrosion monitoring assembly having apressure assembly and signal conductor according to another exampleembodiment.

FIG. 5 is a perspective view of a wet pipe sprinkler system having acorrosion monitoring assembly according to another example embodiment ofthis disclosure.

FIG. 6 is a perspective view of a dry pipe sprinkler system having acorrosion monitoring assembly according to another example embodiment.

FIG. 7 is a front view of an annunciation device according to anotheraspect of the present disclosure.

FIG. 8 is a side cross-section view of a corrosion monitoring assemblyhaving optional gas and water traps according to another aspect of thepresent disclosure.

FIG. 9 is a side view of a water supply system including a corrosionmonitoring assembly.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

According to one aspect of the present disclosure, a fire sprinklersystem includes a pipe having a first pipe portion and a second pipeportion. The first pipe portion includes a wall having a first wallthickness, and the second pipe portion includes a wall having a secondwall thickness that is greater than the first wall thickness. The firesprinkler system further includes structure coupled to the pipe anddefining a sealed chamber between the structure and the first pipeportion, and a sensor for sensing a pressure in the sealed chamber.

According to another aspect of the present disclosure, a corrosionmonitoring device for a fire sprinkler system includes a pipe havingopposite ends and a middle portion positioned between the opposite ends.The opposite ends of the pipe each include a wall having a first wallthickness, and the middle portion of the pipe includes a wall having asecond wall thickness that is less than the first wall thickness. Thecorrosion monitoring device further includes structure coupled to thepipe and defining a sealed chamber between the structure and the pipe,and a sensor for sensing a pressure in the sealed chamber.

According to yet another aspect of the present disclosure, a method ofinstalling a corrosion monitoring device in a fire sprinkler systemhaving a pipe is disclosed. The method includes removing a section ofthe pipe from the fire sprinkler system to create two pipe ends with aspace between, positioning the corrosion monitoring device in the space,and coupling the corrosion monitoring device to the two pipe ends.

According to another aspect of the present disclosure, a fire sprinklersystem includes a pipe having a first pipe portion and a second pipeportion. The first pipe portion includes a wall having a first wallthickness, and the second pipe portion includes a wall having a secondwall thickness. The fire sprinkler system also includes structurecoupled to the pipe and defining a sealed chamber between the structureand the first pipe portion, and a sensor for sensing a parameterassociated with the sealed chamber.

According to yet another aspect of the present disclosure, a corrosionmonitoring device for a fire sprinkler system includes a pipe havingopposite ends and a middle portion positioned between the opposite ends.The opposite ends of the pipe each include a wall having a first wallthickness, and the middle portion of the pipe includes a wall having asecond wall thickness. The corrosion monitoring device further includesstructure coupled to the pipe and defining a sealed chamber between thestructure and the first pipe portion, and a sensor for sensing aparameter associated with the sealed chamber.

According to another aspect of the present disclosure, a method ofmonitoring corrosion within a fire sprinkler system having a pipe, andstructure coupled to the pipe and defining a sealed chamber between thestructure and the pipe, is disclosed. The method includes sensing, witha pressure sensor, a pressure within the sealed chamber. The method alsoincludes detecting a change in pressure within the sealed chamber,corresponding to a breach of a pipe wall of the sealed chamber. Themethod further includes generating a signal in response to detecting thechange in pressure within the sealed chamber.

According to yet another aspect of the present disclosure, a method ofmonitoring corrosion within a fire sprinkler system having a pipe, andstructure coupled to the pipe and defining a sealed chamber between thestructure and the pipe, is disclosed. The method includes sensing aparameter associated with the sealed chamber, and detecting a change inthe parameter associated with the sealed chamber, corresponding to abreach of a pipe wall of the sealed chamber. The method also includesgenerating a signal in response to detecting the change in the parameterassociated with the sealed chamber.

Further aspects and areas of applicability will become apparent from thedescription provided herein. It should be understood that variousaspects of this disclosure may be implemented individually or incombination with one or more other aspects. It should also be understoodthat the description and specific examples herein are intended forpurposes of illustration only and are not intended to limit the scope ofthe present disclosure.

DETAILED DESCRIPTION

One example embodiment of a fire sprinkler system according to thepresent disclosure is illustrated in FIG. 1 and indicated generally byreference number 100. As shown in FIG. 1, the fire sprinkler system 100includes a pipe 102 including a first pipe portion 104 and a second pipeportion 106. The first pipe portion 104 includes a wall having a firstwall thickness T1, and the second pipe portion 106 includes a wallhaving a second wall thickness T2 that is greater than the first wallthickness T1. The fire sprinkler system 100 further comprises structure108 coupled to the pipe 102 and defining a sealed chamber 110 betweenthe structure 108 and the first pipe portion 104. The system 100 alsoincludes a sensor for sensing a pressure in the sealed chamber 110.

Because the first pipe portion 104 includes a wall with a lesser wallthickness T1 as compared to the second pipe portion (and optionally anyother pipe portion in the fire sprinkler system), any breach through apipe wall in the fire sprinkler system due to corrosion should occurfirst in the first pipe portion 104. Such a breach will cause a pressurechange in the sealed chamber 110 and can be detected by the sensor. Inthat event, corrective action can be taken before the overall system 100is breached and allows water to escape, which would potentially (orlikely) result in expensive damage, business interruption, etc.

The first pipe portion 104 may have the same material composition as thesecond pipe portion 106 (and/or the third pipe portion discussed below)so various pipe portions are equally subject to corrosion (i.e., ifsubjected to the same environmental conditions). The pipe portions maycomprise black steel, galvanized steel, stainless steel, copper and/orother suitable material(s).

The first pipe portion 104 and the second pipe portion 106 (and thethird pipe portion) may have the same inner diameter, and preferablyhave or contain no obstructions that could impede the flow of watertherethrough.

Optionally, the first pipe portion 104 may be substantially identical tothe second pipe portion 106 (and the third pipe portion) in everyrespect, except for the lesser wall thickness T1 of the first pipeportion 104. For example, the pipe portions may have the same materialcomposition, the same inner diameter, the same interior surface texture,the same galvanized layer (if applicable), the same weld seam (ifapplicable) positioned in the same orientation (i.e., the same“clocking”), etc. As a result, the interior surface of the first pipeportion 104 may experience the same corrosion process as the second pipeportion 106 (and the third pipe portion), and may therefore constitutean accurate gauge of any corrosion damage in the second pipe portion106, the third pipe portion and/or other pipe portions in the firesprinkler system 100.

The wall thickness of the second pipe portion 106 (i.e., thickness T2)may gradually lessen to the thickness of the first pipe portion 104(i.e., thickness T1) at milled shoulders 105.

In the particular embodiment shown in FIG. 1, the sealed chamber 110extends around the circumference of the first pipe portion 104. As aresult, the entire circumference can be monitored for a breach due tocorrosion. Alternatively, the sealed chamber 110 may extend about only aportion of the first pipe portion, preferably including the bottom sideof the first pipe portion 104 (i.e., at the six o'clock position) or thetop side of the first pipe portion 104 (i.e., at the twelve o'clockposition) where a breach due to corrosion may be most likely to occur(which may depend on whether the system 100 is a dry pipe or wet pipefire sprinkler system). In the particular embodiment shown in FIG. 1,the height of the sealed chamber 110 from the outer surface of the firstpipe portion 104 is constant around the circumference of the first pipeportion 104, but in other embodiments the height of the sealed chamber110 may vary along portions of the pipe.

As shown in FIG. 1, the pipe 102 includes a third pipe portion 114similar to the second pipe portion 106. The structure 108 is coupled tothe first pipe portion 104 via welding (i.e., at weld joints 109) onopposite sides of the wall having the thinner wall thickness T1, and atlocations having the same wall thickness T2 as the second and third pipeportions 106, 114. Alternatively, the structure 108 may be coupled tothe first pipe portion 104 in another suitable manner (i.e., withoutwelding), at other suitable locations of the first pipe portion 104,and/or may be coupled to the second and/or third pipe portions 106, 114to define the sealed chamber 110.

As further shown in FIG. 1, the structure 108 may include a sleevehaving an inner diameter that is greater than the outer diameter of thefirst, second and third pipe portions 106, 114. Further, the sleeve maybe coaxial with the first pipe portion 104 and have the samecross-sectional shape (i.e., circular). Alternatively, the structure 108can have various other configurations for forming the sealed chamber110, and may not include a sleeve.

In the example shown in FIG. 1, the first pipe portion 104, structure108, sealed chamber 110 and sensor constitute a corrosion monitoringassembly that is coupled to the second and third pipe portions 106, 114via roll grooved and/or cut grooved couplings 111, which may includegaskets 113. Alternatively, the corrosion monitoring assembly may becoupled to the second and/or third pipe portions via other suitablemeans, such as threaded couplings, welding, etc.

The first pipe portion may have opposite ends and a middle portionpositioned between the opposite ends. The opposite ends of the pipe eachmay include a wall having a first wall thickness, and the middle portionof the pipe may include a wall having a second wall thickness. Thesecond wall thickness may be less than the first wall thickness.Alternatively, the first and second wall thicknesses may be the same(i.e., no lesser wall thickness).

As another alternative, the first, second and third pipe portions mayconstitute a single, continuous piece of pipe (having different wallthicknesses along its length), with the corrosion monitoring assemblyformed integrally therewith (e.g., when the fire sprinkler system 100 isfabricated and installed), rather than separate pipe sections that arecoupled together.

As yet another alternative, the corrosion monitoring assembly may extendalong the entire length of the pipe 102. In that event, the assembly mayinclude two or more sealed chambers for detecting breaches due tocorrosion in various regions of the pipe 102.

Pipe 102 may include multiple corrosion monitoring assemblies, which maybe used to detect corrosion at multiple locations along pipe 102.Alternatively, or in addition, one or more corrosion monitoringassemblies may be provided on other pipes in the system 100 (i.e., inaddition to pipe 102).

The corrosion monitoring assembly may have substantially the samepressure rating (i.e., the pressure rating of the first pipe portion 104of the corrosion monitoring assembly) as one or more pipes in the system100 (i.e., including pipe 102), or may have a greater or lesser pressurerating. In some example embodiments, the corrosion monitoring assemblymay have a pressure rating of about 175 PSIG.

The sensor may be any suitable type of sensor for sensing a pressure inthe sealed chamber 110. For example, the sensor may be an electronicpressure transducer, a pneumatic sensor, a pressure switch (e.g., a ULlisted and/or FM approved pressure switch for use in fire sprinklersystems), etc. Further, the sensor may be positioned in the sealedchamber 110, or may be coupled to the sealed chamber 110 via adiaphragm, pressure tubing, or other suitable means. In the particularembodiment shown in FIG. 1, the structure 108 includes a sleeve definingthe sealed chamber 110, and the sensor includes (i) a pressure tubingconnector 112 (e.g., a ¼ inch male national pipe thread taper (MNPT))coupled to a port 116 (e.g., a ¼ inch female national pipe thread taper(MNPT)) in the sleeve defining the sealed chamber 110, (ii) pressuretubing 115 coupled to the pressure tubing connector 112, and (iii) apressure switch or transducer (not shown) coupled to the pressuretubing. As should be apparent, however, numerous other sensorconfigurations may be employed without departing from the teachings ofthis disclosure. For example, if the system 100 is a wet pipe sprinklersystem, the sensor may be configured to detect the presence or absenceof a liquid (i.e., instead of or in addition to sensing a pressure) inthe sealed chamber, where the detection of a liquid would indicate abreach through the first pipe portion 104.

Additionally, or alternatively, the sensor may be configured to producean analog and/or digital signal representing a pressure (including achange in pressure) or other parameter in the sealed chamber 110, suchas the absence or presence of a liquid, temperature, etc. Further, thesensor may be connected via a wired and/or wireless communicationchannel to a fire alarm panel, a building management system and/or acorrosion monitoring station (e.g., onsite or offsite), which maygenerate alarm(s) and/or take other appropriate action(s) in response todetecting a breach through the wall of the first pipe section 104. Forexample, the sensor may be a pressure switch including a dry contactwired to a monitoring station.

The fire sprinkler system 100 may be of any desired type orconfiguration, including a wet pipe system and a dry pipe system(including preaction systems). In some embodiments, the fire sprinklersystem 100 may be substantially filled with water and/or an inert gas(e.g., nitrogen) to inhibit corrosion in the fire sprinkler system.

A method of making a corrosion monitoring assembly according to anotherexample embodiment is illustrated in FIGS. 2 and 3. In particular, FIG.2 illustrates a length of what is referred to as “two inch” schedule 40black steel pipe 104, having an external dimension of about 2.38 inches,an internal dimension of about 2.07 inches, a nominal thickness of about0.154 inches (154 mils), a length of about twelve inches, and a rolledgroove end finish.

FIG. 3 illustrates a length of “2½ inch” schedule 40 black steel pipe108, having an external dimension of about 2.88 inches, an internaldimension of about 2.47 inches, a nominal thickness of about 0.203inches (203 mils), a length of about three inches, and a straight cutend finish. As shown in FIG. 2, a portion of the two inch pipe 104 maybe milled down (e.g., via a lathe), or otherwise formed, to create anarea having a reduced wall thickness T1 (preferably with milledshoulders 105 on both ends of the milled section, as shown in FIGS. 2and 3). The reduced wall thickness may be about 20-30 mils, and may beabout two inches in length, although it should be understood that otherreduced wall thicknesses and/or lengths may be used in otherembodiments. The 2½ inch pipe 108 constitutes a sleeve that is centeredover the reduced wall thickness portion of the two inch pipe 104 andwelded in place, preferably to non-“reduced” portions, as shown in FIG.3 at weld joints 109. Optionally, the assembly may be subjected to heatannealing to eliminate any heat affected zones created by the welding. Atapped port 116 is formed in the sleeve 108 (e.g., tapped in the centerof the sleeve 108) for attaching a sensor (not shown), a pressure tubingconnector (not shown), etc., to facilitate sensing a pressure and/orother parameter in the sealed chamber 110 formed between the outersleeve 108 and the inner pipe 104. Optionally, the sealed chamber 110may be pressure tested to verify its integrity and the absence of anyleaks before the assembly is placed into service.

The corrosion monitoring assembly may be installed in a fire sprinklersystem at a location most susceptible to corrosion (e.g., where water islikely to collect in a dry pipe system, where air is likely trapped in awet pipe system, etc.). For example, the fire sprinkler system (or otherpipe system) can be analyzed (e.g., using a scope) to identify suchlocations before installing corrosion monitoring devices at suchlocations.

To install the corrosion monitoring assembly in a preexisting firesprinkler system, a section of pipe may be cut and removed from thepreexisting system (e.g., from a location most susceptible to corrosionas noted above). For example, if the corrosion monitoring assembly isabout eighteen inches in length, an eighteen inch section of pipe may beremoved from the preexisting system. The corrosion assembly may beselected based on the characteristics of the pipe in the preexistingsystem (e.g. the inner pipe has the same schedule, type of steel, innerdiameter, etc.). Optionally, the removed section of pipe may be used tofabricate the first pipe portion 104 of a corrosion monitoring assembly.In that event, the existing pipe sections to which the corrosionmonitoring assembly will be coupled will have the same characteristicsas the first pipe portion 104 (except for the reduced wall thickness ofthe first pipe portion 104), including any preexisting corrosion damage.The remaining ends of the preexisting system pipe may be roll groovedprior to installation of the corrosion monitoring device to assist inconnecting the grooved end type couplings of the corrosion monitoringdevice. The exterior surface of the assembly may receive a powder coatfinish, which may correspond to the powder coat finish of thepreexisting system pipe.

The various corrosion monitoring devices described herein may beinstalled “in situ” within a piping system, meaning each monitoringdevice may be installed in an active portion of the system. For example,in a water-based fire sprinkler system, each corrosion monitoring devicemay be installed in the flow path between the water source for thesystem and one or more sprinkler heads.

According to another example embodiment, FIG. 4 illustrates a corrosionmonitoring assembly 400 having a first pipe portion 104 coupled betweena second pipe portion 106 and a third pipe portion 114. A sleeve 108 isattached to the first pipe portion 104 via welds 109 to create a sealedchamber (not shown). A pressure assembly 118 is coupled to the sleeve108 via port 116 of the sleeve 108. The pressure assembly 118 mayinclude a pressure switch, pressure transducer, etc., for detecting apressure inside the sealed chamber. A signal conductor 120 outputs asignal from the pressure assembly 118. The signal conductor may be awire and may be coupled to a local indicator, a fire alarm panel, abuilding management system, monitoring station, etc. Alternatively, orin addition, the pressure assembly 118 may output signals wirelessly.The pressure assembly 118 may continuously output a signal correspondingto the pressure level inside the sealed chamber. Alternatively, or inaddition, the pressure assembly 118 may output a signal when a change inpressure (or another parameter of interest) occurs.

FIG. 5 illustrates two corrosion monitoring assemblies 400 of FIG. 4 inan example wet pipe fire sprinkler system 500. As shown in FIG. 5, thewet pipe fire sprinkler system includes a source of gas 152 (e.g., anitrogen gas cylinder) coupled to the piping network near a water valve154 on a riser of the fire sprinkler system 500. A wet pipe vent 156 iscoupled to the piping network to allow gas but not water to escape thepiping network. The wet pipe vent 156 is connected to a vent indicator158 to indicate a gas concentration within the piping network (e.g., alevel of nitrogen gas in the piping network). A pressure assembly 118 ofeach corrosion monitoring assembly 400 is connected to a local indicator122 (alternatively, or in addition to, a fire alarm panel, buildingmanagement system, monitoring station, etc.) via a signal conductor 120(e.g., an electrical conductor). Although two corrosion monitoringassemblies 400 are included in example fire sprinkler system 500, itshould be understood that more or less corrosion monitoring assembliesmay be included in other embodiments.

FIG. 6 illustrates the corrosion monitoring assembly 400 of FIG. 4 in anexample dry pipe fire sprinkler system 600. As shown in FIG. 6, the drypipe fire sprinkler system 600 includes a generator 162 (e.g., anitrogen generator) to provide pressurized gas to the piping network,near a water valve 154 on a riser of the fire sprinkler system 600. Adry pipe vent 164 is coupled to the piping network near the water valve154 on the riser to allow gas but not water to escape the pipingnetwork. The dry pipe vent 164 is coupled to a vent indicator 158 toindicate a gas concentration within the piping network (e.g., a level ofnitrogen gas in the piping network). A pressure assembly 118 of thecorrosion monitoring assembly 400 is coupled to a local indicator 122(alternatively, or in addition to, a fire alarm panel, buildingmanagement system, monitoring station, etc.) via signal conductor 120.Although only one corrosion monitoring assembly 400 is included in thefire sprinkler system 600, it should be understood that multiplecorrosion monitoring assemblies may be coupled to the dry pipe firesprinkler system 600 to detect corrosion at multiple locations in thefire sprinkler system.

Further, the various corrosion monitoring devices described herein mayinclude one or more audible indicators (e.g., buzzers) and/or one ormore visual indicators (e.g., indicator lights) to provide alerts when asensor detects a breach in the sealed chamber (i.e., instead of or inaddition to sending a signal to a fire alarm panel, a buildingmanagement system and/or a corrosion monitoring station as describedabove). Additionally, a test button may be included that, whenactivated, illuminates the visual indicator(s) and/or sounds the audibleindicator(s) to verify the integrity and/or proper operation of theindicator(s), the overall assembly and/or the power source(s). Thecorrosion monitoring devices may also be adapted to provide a visualand/or audible indication (such as a flashing light or beeping sound)when an internal power source (e.g., a battery) requires service orreplacement, when external power is removed, etc.

FIG. 7 illustrates an example annunciation device 700 that includes avisual indicator, an audible indicator and a test button. The device 700may be directly coupled to a corrosion monitoring device (e.g., viaelectric cable, pressure tubing, etc.). Alternatively, or in addition,the device 700 may be coupled to a fire alarm panel, a buildingmanagement system and/or a remote corrosion monitoring station forreceiving signals indicating the sensor detected a breach and, inresponse, activating the audible and/or visual indicators. The device700 may include an internal power source (e.g., a lithium ion batterypack) and/or may be coupled to an external power source (e.g., utilitypower). The internal circuitry (not shown) may be configured such thatno power is consumed until the sensor detects a breach. In theparticular example shown in FIG. 7, the annunciation device 700 includesa housing 702 that may be mounted to its associated corrosion monitoringdevice or elsewhere, such as to a beam, wall or joist. The annunciationdevice 700 may also be adapted for mounting to a ceiling (e.g., to aceiling tile) or other architectural or structural feature that mayobstruct a direct line of sight from the floor (or other vantage pointof an inspector) to the corrosion monitoring device, so the annunciationdevice is visible from the inspector's vantage point even if thecorrosion monitoring device is not.

Each corrosion monitoring device may have a constant inner diameter thatis the same as the system piping to which the monitoring device iscoupled, as shown in FIG. 1. Alternatively, a corrosion monitoringdevice may have an inner diameter that is less than, or greater than,the inner diameter of the adjoining system piping.

FIG. 8 illustrates a corrosion monitoring device 800 having a centersection with an inner diameter that is greater than the inner diameterof the adjacent system piping 104. As a result, the device 800 includesan artificial low point that functions as a “water trap” 824 above aportion of the sealed chamber 110, as well as an artificial high pointthat functions as a “gas trap” 822 below a portion of the sealed chamber110. Because the device 800 is designed to trap water and gas, thedevice 800 may experience more corrosion than other piping in thesystem, regardless of where the device 800 is located in the firesprinkler system. The device 800 is well suited for dry pipe sprinklersystems and wet pipe sprinkler systems. In dry pipe sprinkler systems,the water trap may collect any residual water in the system andtherefore represent the mostly likely site of corrosion (i.e., aroundthe six o'clock position). In wet pipe sprinkler systems, the gas trapmay collect any gas (including oxygen) in the system and thereforerepresent the mostly likely site of corrosion (i.e., around the twelveo'clock position). In other embodiments, the corrosion monitoring devicemay be provided with a water trap or an air trap (but not both).

FIG. 9 illustrates an example water supply system 900 including a pumpassembly 902, pipes 908, and a corrosion monitoring assembly 400 coupledto the water supply system 900. The pump assembly 902 includes a waterpump 904. The corrosion monitoring assembly 400 is coupled to the pipes908 of the water supply system 900 and may be configured to monitorcorrosion at a point where water exits the pump assembly 902. Thecorrosion monitoring assembly 400 includes a pressure assembly 118,which may output signals to a local indicator, fire alarm panel,building management system, monitoring station, etc., via signalconductor 120.

According to another aspect of the present disclosure, a method ofmonitoring corrosion within a fire sprinkler system having a pipe, andstructure coupled to the pipe and defining a sealed chamber between thestructure and the pipe, is disclosed. The method includes sensing (e.g.,using a suitable sensor such as a pressure sensor, conductance probe,temperature sensor, etc.) a parameter associated with the sealed chamber(e.g., a pressure within the sealed chamber, an absence or presence of aliquid, temperature, etc.). The method also includes detecting a changein the parameter associated with the sealed chamber (e.g., a change inpressure), corresponding to a breach of a pipe wall of the sealedchamber. The method further includes generating a signal in response todetecting the change in the parameter. The signal may be indicative ofthe change in the parameter (e.g., magnitude of the change, direction ofthe change, etc.). The signal may optionally be transmitted to a localindicator, a fire alarm panel, a building management system, monitoringstation, etc.

After a sensor detects a breach in the sealed chamber of a corrosionmonitoring assembly, the assembly may be evaluated (in situ or followingremoval from the system) to determine the cause and/or extent of thecorrosive attack. This may include identifying the type(s) of pitsformed in the assembly and/or the pit depth, density, distribution, etc.Corrective action may be recommended for and/or performed on the system,possibly including coupling a nitrogen source to the system, replacing anitrogen source (such as a faulty nitrogen generator), removing oxygenfrom the system (using vents, nitrogen and/or other means), drainingand/or filling the system, replacing one or more pipes in the network,installing one or more corrosion monitoring devices in the system, etc.,and providing instructions for one or more of these actions. Theassembly may be easily replaced by another assembly after a breachoccurs.

Although the example embodiments described above are specific towater-based fire sprinkler systems, it should be understood that theteachings of the present disclosure are applicable to any pipe system,including pressurizable and non-pressurized pipe systems, and aretherefore not limited to fire sprinkler systems.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. Individual elements or featuresof a particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the disclosure, and all such modificationsare intended to be included within the scope of the disclosure.

The invention claimed is:
 1. A water-based fire sprinkler systemcomprising: a water source; one or more sprinkler heads; a corrosionmonitoring device configured to be positioned in a flow path between thewater source and the one or more sprinkler heads, the corrosionmonitoring device including a first pipe having opposite ends and amiddle portion including a wall having a first wall thickness, astructure coupled to the first pipe and defining a sealed chamberbetween said wall of the middle portion and an outermost wall of thestructure, and a sensor to sense a pressure in the sealed chamber, theopposite ends of the first pipe each including a wall having a secondwall thickness; and a second and a third pipe coupled to the oppositeends of the first pipe, the second and third pipes each including a wallhaving a thickness greater than the first wall thickness; wherein thesecond wall thickness is greater than the first wall thickness; whereinthe first, second and third pipes are each rigid pipes comprising blackiron or galvanized steel; wherein a change in the pressure in the sealedchamber corresponds to a breach of said wall of the middle portion dueto corrosion.
 2. The system of claim 1, wherein the opposite ends of thefirst pipe each have an outer diameter, and wherein the structureincludes a sleeve having an inner diameter greater than the outerdiameter.
 3. The system of claim 2, wherein the first pipe includes awall that gradually transitions from the first wall thickness to thesecond wall thickness adjacent opposite ends of the first pipe to definetapered shoulders between the middle portion and the opposite ends ofthe first pipe.
 4. The system of claim 1, wherein the second and thirdpipes are coupled to the opposite ends of the first pipe via a rollgrooved coupling, a cut grooved coupling, a threaded coupling and/orweld(s).
 5. The system of claim 1, wherein the corrosion monitoringdevice includes a water trap positioned above a portion of the sealedchamber.
 6. The system of claim 1, wherein the sealed chamber ispositioned between the structure and at least a twelve o'clock positionof the first pipe.
 7. The system of claim 1, wherein the sensor isconnected via a wired and/or wireless communication channel to abuilding management system.
 8. The system of claim 1, wherein the sensoris connected via a wired and/or wireless communication channel to acorrosion monitoring station.
 9. The system of claim 1, wherein thesealed chamber extends around a circumference of the first pipe.
 10. Thesystem of claim 1, wherein the structure is coupled to the first pipevia welds.
 11. The system of claim 1, wherein the sensor is configuredto produce an analog and/or digital signal representing a pressure or achange in pressure in the sealed chamber.
 12. The system of claim 11,wherein the sensor includes a pressure transducer.
 13. The system ofclaim 11, wherein the sensor includes pressure tubing.
 14. The system ofclaim 11, wherein the sensor includes a pressure switch.
 15. The systemof claim 1, wherein the sensor is connected via a wired and/or wirelesscommunication channel to a fire alarm panel.
 16. The system of claim 1,wherein the sealed chamber is positioned between the structure and atleast a six o'clock position of the first pipe.
 17. The system of claim1, wherein the structure includes a port extending to the sealedchamber, and wherein the sensor includes a pressure tubing connectorcoupled to the port and pressure tubing coupled to the pressure tubingconnector.
 18. The system of claim 1, wherein the fire sprinkler systemis a wet pipe system.
 19. The system of claim 1, wherein the firesprinkler system is a dry pipe system.
 20. The system of claim 1,wherein the corrosion monitoring device includes a gas trap positionedbelow a portion of the sealed chamber.